<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <script src="https://cdn.bootcss.com/jquery/3.4.1/jquery.min.js"></script>
    <script>
        $(function() {
            $("#div01").css("background-color", "red");
            $("img").addClass("img01");
            $("#li01").next().addClass("li");
        });
    </script>
    <style>
        .img01 {
            width: 200px;
            height: 200px;
            border: deeppink 5px solid;
        }
        
        .li {
            font-family: 'Franklin Gothic Medium', 'Arial Narrow', Arial, sans-serif;
            font-size: 24px;
            font-weight: bolder;
        }
    </style>
</head>

<body>
    <DIV id="div01">div01</DIV>
    <img src="image/2019-11-28_104736.png" width="100px" height="100px" />

    <ul>
        <li>水电费水电费</li>
        <li id="li01">水电费水电费</li>
        <li>水电费水电费</li>
        <li>水电费水电费</li>
    </ul>
</body>

</html>